Azo dyestuffs



Patented Aug. 23, 1938 UNITED STATES AZO DYEST'UFFS Hans Roos, Leverkusen-I. G.-Werk, Germany, as-

signor to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application January 30, 1935, Se-

rial No. 4,185. In Germany February 9, 1934 4 Claims.

The present invention relates to new azo dyestuffs, more particularly it relates to dyestufis which are characterized by containing in the molecule in o-position to an azo group an aminoaroylamino or an aminoaroylaminoaroylamino group.

In accordance with the present invention new azo dyestuffs which are characterized by containing in o-position to an azo group, either in a diazotization component or in a coupling component, an aminoaroylamino or an aminoaroylaminoaroylamino group, are prepared by starting with an aminoazo dyestuff containing the amino group in o-position to an azo group, condensing the same with a nitroaroylhalogenide, reducing the nitrogroup to the amino group, and, if desired, introducing into the amino group formed an aminoaroyl group in the same manner.

As the new products are substantially intended to find application for dyeing fibres, the components used in their manufacture should be chosen in such a manner that at least one group rendering same soluble in water or aqueous alkalies, such as the sulfonic acid group, is present in the ready dyestufi. Due to the free amino group the new dyestuffs can be subjected in substance or on the fibre to all the reactions known for aminoazo dyestuffs. Thus, they can be diazotized in substance or on the fibre and coupled with azo dyestuif coupling components; further ther, I wish it to be understood that all the derivatives prepared in the usual manner from my new dyestuffs fall within the scope of the present invention.

The new dyestuffs generally dye the vegetable fibre various shades which are well dischargeable both with a neutral and with an alkaline discharge paste, while a large number of the known comparable dyestuifs containing the aminobenzoylamino group in p-position to theazo group compound which is separted from the hot solution by salting out. The p-amino-benzoyl-o-aminoazobenzene-3-sulfonic acid is again aminobenzoylated in the same manner as described above.

The dyestufi" having in the free state the following formula:

dyes cotton yellow shades which after diazotizing and developing with 1-phenyl-3-methyl-5-pyrazolone yield a full yellow and with p-naphthol an orange. The shades are well dischargeable both with a neutral or alkaline discharge paste.

Example 2.-39.9 kgs. of o-aminodisazobenzene-4-sulfonic acid are condensed with an equimolecular proportion of p-nitrobenzoylchloride and reduced with sodium sulfide, as described in Example 1. the free state the following formula:

they can be prepared according to the process described in my application for Letters Patent, Serial No. 4,186, filed January 30, 1935, entitled Process for the manufacture of azo dyestuffs, by reacting upon" an aromatic nitro-compound with an aromatic o-diamine at elevated temperature in a solvent. It is self-understood that there can be used any o-amino dyestuffs,mono-azo dyestuffs as Well as disand poly-azo dyestuffs. Furimam-O dyes cotton somewhat more reddish-yellow shades than the dyestuff described in Example 1; on diazotizing and developing on the fibre with 1- phenyl-3-methyl-5-pyrazolone, there is obtained a yellow, and with p-naphthol an orange. The dyeings have an excellent dischargeability.

Example 3.-32 kgs. of the sodium salt of paminobenzoyl --o aminoazobenzene 3' sulfonic acid, prepared in accordance with Example 1, are

The dyestuff obtained having in .which dyestufi, it is self-understood, can no dissolved in water, an aqueous solution of 7 kgs. of sodium nitrite is added thereto, and while stirring, 28 litres of hydrochloric acid of B. are introduced. After two hours stirring the diazotization is complete. The diazotization mixture is then poured into an aqueous solution of 362 kgs. of 2-(p-aminobenzoylamino) -5-naphtho1-7-sulfonic acid to which solution 28 kgs. of soda have been added. For completing the cou pling, the reaction mixture is stirred during the night; the dyestuff formed is filtered and dried. The dyestuif having in the free state the following formula:

By developing the dyestuff of the formula of paragraph 1 with l-(p-aminophenyl)-3-methyl- S-pyrazolone, there is obtained a more reddishyellow.

Example 5.The azo dyestufi prepared from 2- nitronaphthalene-4.8-disulfonic acid and o-phenylenediamine according to the process of my application for Letters Patent Serial No. 4,186,

filed January 30, 1935, entitled Process for the manufacture of azo dyestuffs, is transformed into the p-aminobenzoyl compound, as described in Example 1; 57.1 kgs. of the p-aminobenzoylated product are diazotized, as described in Example is obtained in form of an orange-red powder, dyeing the'vegetable fibre orange-red shades which can be'diazotized and coupled on the fibre with p-naphthol to a reddish-orange of excellent tinctorial properties, especially a good dischargeability both with a neutral and alkaline discharge paste.

HOaS

SOzH NHO0C N=N(3H 1 1 II o is pressed and dried. It dyes the fibre greenishyellow shades, which tint remains unchanged when developing with 1-pheny1-3-methyl-5- pyrazolone. The dyeing exerts excellent fastness properties and can be discharged to a pure white.

If instead of m-aminophenylmethylpyrazolone there is used 1-phenyl-3-methyl-5pyrazolone, a

dyestuff exerting similar properties is obtained,

more be developedon the fibre.

3, andthe diazotizationmixture is poured into an aqueous solution of 48 kgs. of 2-(m-aminobenzoyl -m-aminobenzoyl) -amino-5-naphthol-7sulfonic acid, to which solution 28 kgs; of soda have been added. The dyestufi obtained having'in the free state the following formula:

in Example 1, but on developing on the fibre with p-naphthoLyields more yellow shades.

If instead I of 2- (m-aminobenzoyl-meaminobenzoyl) -amino-5-naphthol-7sulfonic acid there..

is used 2- (acetylamino) -5-naphthol-7-sulfonic acid, a dyestufi yielding similar shades, but which cannot be developed on the fibre, is obtained.

I claim: 1. Azo dyestufis of the general formula:

wherein A stands for a member selected from'the group consisting of radicals of the naphthalener and benzene series free from a hydroxy or an amino group, B stands .for a radical .oftthewbenzene series free from ahydroxy-group and .further amino and azo groups, R and R standfor radicals of the benzene series and n stands .for one or .zero, andwherein X stands for v.a:;memb.er selected from the group consisting of..the.amino group and the group N.=NR:, wherein 1 R" meansa radical of an azo dyestufi. couplingv component, dyeing the vegetable fibre :various. shades .40 has properties similar to those of. that described" which are well dischargeable both with a neutral and with an alkaline discharge paste.

SOaH

2. A20 dyestuffs of the general formula:-

wherein A stands for a radical of the benzene or naphthalene series free from a hydroxy or an amino group and D stands for the radical of a diazotizable azo dyestuff coupling component.

3. The azo dyestufi having in its free state the following formula:

NH-CO- N=N- a Q Q A 5 dyeing the vegetable fibre yellow shades which after diazotizing and developing with p-naphthol are turned to a yellowish orange.

HANS R008. 35 

